This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The effect of obesity on drug metabolism in children is poorly understood. Therefore, the overall objective of this study is to better understand the effect of weight on drug metabolism in the pediatric population.